Significant progress has been made in the development of thin-film organic electronic devices such as photovoltaic cells, transistors, photodetectors, sensors, and other devices for commercial application. Many of these devices utilize solution-processable semiconductors based on fullerene derivatives in pure form. The most commonly used fullerene derivative is phenyl-C61-butyric-acid-methyl-ester (PCBM), which is classified as a methanofullerene.
PCBM is an analogue of [60]PCBM from C60 fullerene. [70]PCBM has been used as a semiconductor in organic electronics, particularly for polymer solar devices (WIENK et al., Angewadte Chemie, 2003, (115), 3493-3497) and transistors (Anthopoulos et al., Journal of Applied Physics, (98), 054503).
Previous methods for obtaining PCBM have resulted in a yield of 35% at most (Hummelen et al., J. Org. Chem 1995, 60, 532). In the production method of Yang et al., Carbon 2007, 45, 2951, the yield of PCBM was only 33.6% at most.
A higher yield of PCBM is greatly desired due to its widespread use as a solution-processable semiconductor for thin-film organic electronic devices.